Pesticidal 3-phenoxybenzyl α-cyclopropyl α-phenyl-acetates

ABSTRACT

α-Phenyl-α-cyclopropylacetates of the formula ##STR1## wherein X 1  represents hydrogen, halogen or C 1  -C 4  alkyl, X 2  represents hydrogen, methyl or halogen, R 1  represents hydrogen, cyano, vinyl or ethynyl, and Y represents fluorine or bromine, processes for their manufacture, and a method of controlling pests which comprises the use of these novel esters.

The present invention relates to α-phenyl-α-cyclopropylacetates,processes for their manufacture, and a method of controlling pests whichcomprises the use of these novel esters.

The α-phenyl-α-cyclopropylacetates have the formula ##STR2## wherein X₁represents hydrogen, halogen or C₁ -C₄ alkyl, X₂ represents hydrogen,methyl or halogen, R₁ represents hydrogen, cyano, vinyl or ethynyl, andY represents fluorine or bromine.

By halogen is meant in this connection fluorine, chlorine, bromine oriodine, but especially chlorine.

Possible alkyl groups X₁ are for example: methyl, ethyl, propyl,isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl. Preferred compoundson account of their action are those of the formula I, wherein X₁represents hydrogen, chlorine or methyl, X₂ represents hydrogen orchlorine, R₁ represents hydrogen, cyano, vinyl or ethynyl, and Yrepresents fluorine or bromine.

The most preferred compounds, however, are those of the formula I,wherein X₁ represents chlorine or methyl, X₂ represents hydrogen, R₁represents cyano or ethynyl, and Y represents o-fluorine, m-fluorine orp-fluorine.

The compounds of the formula I can be obtained by methods which areknown per se, for example as follows: ##STR3##

In the formulae II to VI, X₁, X₂, Y and R₁ are as defined for formula I.

In the formulae III and IV, X represents a halogen atom, especially achlorine or bromine atom, and in formula VI R represents C₁ -C₄ alkyl,especially methyl or ethyl.

Suitable acid acceptors for processes 1 and 2 are in particular tertiaryamines, such as trialkylamine and pyridine, and also hydroxides, oxides,carbonates and bicarbonates of alkali metals and alkaline earth metals,and in addition alkali metal alcoholates, for example potassiumtert-butylate and sodium methylate. As hydrophilic agent for process 3,dicyclohexylcarbodiimide can be used for example. Processes 1 to 4 arecarried out at a reaction temperature between -10° and 120° C., usuallybetween 20° and 80° C., under normal or elevated pressure and preferablyin an inert solvent or diluent. Examples of suitable solvents ordiluents are: ether and ethereal compounds, for example diethyl ether,dipropyl ether, dioxane, dimethoxyethane and tetrahydrofurane; amides,such as N,N-dialkylated carboxamides; aliphatic, aromatic andhalogenated hydrocarbons, especially benzene, toluene, xylenes,chloroform and chlorobenzene; nitriles, such as acetonitrile; dimethylsulfoxide; and ketones, such as acetone and methyl ethyl ketone.

The starting materials of the formulae II to VII are known or they canbe prepared by methods analogous to known ones.

The compounds of the formula I are in the form of a mixture of differentoptically active isomers if individual optically active startingmaterials are not used in the reaction. The different isomer mixturescan be separated into the individual isomers by known methods. Thecompound of the formula I is to be understood as comprising both theindividual isomers and the mixtures thereof. The compounds of theformula I are suitable for controlling a variety of animal and plantpests. In particular, the compounds of the formula I are suitable forcontrolling insects, phytopathogenic mites and ticks, for example of theorders: Lepidoptera, Coleoptera, Homoptera, Heteroptera, Diptera,Acarina, Thysanoptera, Orthoptera, Anoplura, Siphonaptera, Mallophaga,Thysanura, Isoptera, Psocotera and Hymenoptera.

In particular, the compounds of the formula I are suitable forcontrolling insects which are harmful to plants, especially insectswhich damage plants by eating, in ornamentals and crops of usefulplants, especially in cotton plantations (e.g. Spodoptera littoralis andHeliothis virescens) and in vegetable crops (for example Leptinotarsadecemlineata and Myzus persicae).

The active compounds of the formula I also have a very good actionagainst flies, for example Musca domestica and mosquito larvae.

Surprisingly, the compounds of the formula I have a broader insecticidalactivity spectrum than chemically analogous compounds disclosed inGerman Offenlegungsschrift 2 717 414.

The acaricidal and/or insecticidal action can be substantially broadenedand adapted to prevailing circumstances by addition of otherinsecticides and/or acaricides. Examples of suitable additives include:organic phosphorus compounds, nitrophenols and derivatives thereof,formamidines, ureas, pyethroids, carbamates, and chlorinatedhydrocarbons.

Compounds of the formula I are also combined with particular advantagewith substances which exert a synergistic or potentiating effect onpyrethroids. Examples of such compounds include: piperonyl butoxide,propynyl ether, propynyl oximes, propynyl carbamates and propynylphosphates, 2-(3,4-methylenedioxyphenoxy)-3,6,9-trioxaundecane (Sesamexor Sesoxane), S,S,S-tributylphosphorotrithioate,1,2-methylenedioxy-4(2-(octylsulfinyl)-propyl)-benzene.

The compounds of the formula I may be used as pure active substance ortogether with suitable carriers and/or adjuvants. Suitable carriers andadjuvants can be solid or liquid and correspond to the substancesconventionally used in the art of formulation, for example natural orregenerated substances, solvents, dispersants, wetting agents,tackifiers, thickeners, binders and/or fertilisers.

The compositions of the present invention are manufactured in knownmanner by homogeneously mixing and/or grinding active substances of theformula I with the suitable carriers, with or without the addition ofdispersants or solvents which are inert to the active substances.

The compounds of the formula I may be processed to the followingformulations:

Solid formulations:

Dusts, tracking powders and granules (coated granules, impregnatedgranules and homogeneous granules).

Liquid formulations:

(a) active substances which are dispersable in water: wettable powders,pastes and emulsions;

(b) solutions.

The content of active substance in the above described compositions isgenerally between 0.1% and 95%, though concentrations of up to 99.5% oreven pure active substance can also be used if the compositions areapplied from an aircraft or other appropriate application devices.

The compounds (active substances) of the formula I can, for example, beformulated as follows (throughout the present specification all partsand percentages are by weight):

DUSTS

The following substances are used to formulate

(a) a 5% and (b) a 2% dust: (a)

5 parts of active substance,

95 parts of talc;

(b)

2 parts of active substance,

1 part of highly disperse silicic acid,

97 parts of talc.

The active substance is mixed with the carriers and ground.

GRANULES

The following substances are used to formulate 5% granules:

5 parts of active substance

0.25 parts of epichlorohydrin,

0.25 parts of cetyl polyglycol ether,

3.50 parts of polyethylene glycol,

91 parts of kaolin (particle size 0.3 -0.8 mm).

The active substance is mixed with epichlorohydrin and the mixture isdissolved in 6 parts of acetone; the polyethylene glycol and cetylpolyglycol ether are then added. The resultant solution is sprayed onkaolin, and the acetone is subsequently evaporated in vacuo.

WETTABLE POWDERS:

The following constituents are used to formulate (a) a 40%, (b) and (c)a 25%, and (d) a 10% wettable powder: (a)

40 parts of active substance,

5 parts of sodium dibutylnaphthalenesulfonate,

54 parts of silicic acid.

(b)

25 parts of active substance,

4.5 parts of calcium ligninsulfonate,

1.9 parts of Champagne chalk/hydroxyethyl cellulose mixture (1:1),

1.5 parts of sodium dibutylnaphthalenesulfonate,

19.1 parts of silicic acid,

19.5 parts of Champagne chalk,

28.1 parts of kaolin,

(c)

25 parts of active substance,

2.5 parts of isooctylphenoxy-polyoxyethyleneethanol,

1.7 parts of Champagne chalk/hydroxyethyl cellulose mixture (1:1),

8.3 parts of sodium aluminium silicate,

16.5 parts of kieselguhr,

46 parts of kaolin;

(d)

10 parts of active substance,

3 parts of a mixture of the sodium salts of saturated fatty alcoholsulfates,

5 parts of naphthalenesulphonic acid/formaldehyde condensate,

82 parts of kaolin.

The active substances are homogeneously mixed with the additives insuitable mixers and the mixture is then ground in appropriate mills androllers. Wettable powders are obtained which can be diluted with waterto give suspensions of the desired concentration.

EMULSIFIABLE CONCENTRATES:

The following substances are used to formulate (a) a 10%, (b) a 25% and(c) a 50% emulsifiable concentrate:

(a)

10 parts of active substance,

3.4 parts of epoxidised vegetable oil,

3.4 parts of a combination emulsifier consisting of fatty alcoholpolyglycol ether and alkylarylsulfonates calcium salt,

40 parts of dimethyl formamide,

43.2 parts of xylene;

(b)

25 parts of active substance,

2.5 parts of epoxidised vegetable oil,

10 parts of alkylarylsulfonate/fatty alcohol polyglycol ether mixture,

5 parts of dimethyl formamide,

57.5 parts of xylene;

(c)

50 parts of active substance,

4.2 parts of tributylphenol-polyglycol ether,

5.8 parts of cylcium dodecylbenzenesulfonate,

20 parts of cyclohexanene,

20 parts of xylene.

By diluting these concentrates with water it is possible to obtainemulsions of the required concentration.

SPRAYS:

The following ingredients are used to formulate (a) a 5% spray, and (b)a 95% spray:

(a)

5 parts of active substance,

1 part of epichlorohydrin,

94 parts of ligroin (boiling range 160°-190° C.);

(b)

95 parts of active substance,

5 parts of epichlorohydrin.

The invention is further illustrated by the following Examples.

EXAMPLE 1 Manufacture of (3-(4-fluorophenoxy)-α-cyanobenzylα-cyclopropyl-4-chlorophenylacetate

With stirring, 1 g of pyridine in 3 ml of toluene and 2.3 g ofα-cyclopropyl-4-chlorophenylacetyl chloride in 3 ml of toluene are addedsuccessively at 0° to 10° C. to a solution of 2.43 g of3-(4-fluorophenoxy)-α-cyanobenzyl alcohol in 20 ml of toluene. Afterstirring for 10 hours at room temperature, the reaction mixture iswashed with water, 2 N hydrochloric acid and 3% sodium bicarbonatesolution. The organic layer is dried over sodium sulfate and the tolueneis distilled off, affording the compound of the formula ##STR4## with arefractive index of n_(D) ²⁰ =1.5880.

The following compounds are prepared in analogous manner:

    __________________________________________________________________________     ##STR5##                      n.sub.D.sup.20° = 1.5851                 ##STR6##                      n.sub.D.sup.20° = 1.5599                 ##STR7##                      n.sub.D.sup.20° = 1.5682                 ##STR8##                      n.sub.D.sup.20° = 1.5650                 ##STR9##                      n.sub.D.sup.20° = 1.5639                 ##STR10##                     n.sub.D.sup.20° = 1.5658                 ##STR11##                     n.sub.D.sup.20° = 1.5678                 ##STR12##                     n.sub.D.sup.20° = 1.5638                 ##STR13##                     n.sub.D.sup.20° = 1.5913                 ##STR14##                     n.sub.D.sup.40° = 1,5571                 ##STR15##                     n.sub.D.sup.40° = 1,5646                 ##STR16##                     n.sub.D.sup.40° = 1,5460                 ##STR17##                     n.sub.D.sup.20° = 1,5627                 ##STR18##                     n.sub.D.sup.20° = 1,5625                 ##STR19##                     n.sub.D.sup.20° = 1,5652                 ##STR20##                     n.sub.D.sup.20° = 1,5883                 ##STR21##                     n.sub.D.sup.20° = 1,5748                 ##STR22##                     n.sub.D.sup.20° = 1,5737                 ##STR23##                     n.sub.D.sup.33° = 1,5573                 ##STR24##                     n.sub.D.sup.33° = 1,5675                 ##STR25##                     n.sub.D.sup.33° = 1,5568                 ##STR26##                     n.sub.D.sup.33° = 1,5663                 ##STR27##                     n.sub.D.sup.33° = 1,5646                 ##STR28##                     n.sub.D.sup.40° = 1,5461                __________________________________________________________________________

EXAMPLE 2 Insecticidal stomach poison action

Cotton plants were sprayed with a 0.05% aqueous emulsion of activesubstance (obtained from a 10% emulsifiable concentrate). After thespray coating had dried, the cotton plants were populated with larvae ofSpodoptera littoralis and Heliothis virescens in the L₃ -stage. the testwas carried out at 24° C. and 60% relative humidity. In this test, thecompounds of Example 1 exhibited a good insecticidal stomach poisonaction against Spodoptera and Heliothis larvae.

EXAMPLE 3 Acaricidal action

Twelve hours before the test for acaricidal action, Phaseolus vulgarisplants were populated with an infested piece of leaf from a mass cultureof Tetranychus urticae. The mobile stages which had migrated to theplants were sprayed with the emulsified test preparations from achromatography atomiser in such a way that the spray broth did not runoff. The number of living and dead larvae, adults and eggs was evaluatedunder a stereoscopic microscope after 2 and 7 days and the resultexpressed in percentage values. During the test run, the plants stood ingreenhouse compartments at 25° C. In this test, the compounds of Example1 acted against adults, larvae and eggs of Tetranychus urticae.

EXAMPLE 4 Action against ticks

(A) Rhipicephalus bursa

Five adult ticks and 50 tick larvae were counted into each of a numberof test tubes and immersed for 1 to 2 minutes in 2 ml of an aqueousemulsion containing a concentration of 100, 10, 1 or 0.1 ppm of testsubstance. Each test tube was then sealed with a cottonwool plug andplaced on its head to enable the cotton wool to absorb the activesubstance emulsion. Evaluation of the action against adults was madeafter 2 weeks and of that against larvae after 2 days. Each test wasrepeated twice.

(B) Boophilus microplus (larvae)

Test were carried out with 20 OP-sensitive and 20 OP-resistant larvaeusing aqueous emulsions similar to those used in Test A. (The resistancerefers to the tolerance towards diazinone). The compounds of Example 1acted in these tests against adults and larvae of Rhipicephalus bursaand OP-sensitive and OP-resistant larvae of Boophilus microplus.

What is claimed is:
 1. A compound of the formula ##STR29## wherein X₁represents chlorine or methyl, R₁ represents cyano or or ethynyl, and Yrepresents o-fluorine or p-fluorine.
 2. The compound according to claim1 of the formula ##STR30##
 3. A insecticidal and acaricidal compositionwhich contains, as active component, a compound according to claim 1 andsuitable carriers.
 4. A method for combatting insects and acarids whichcomprises applying thereto an insecticidally or acaricidally effectiveamount of a compound according to claim
 1. 5. The method according toclaim 4 in which the compound is ##STR31##